Splash developer always had one of the worst support I ever encountered. They either never answer or answer in a few YEARS! Splash player updates are extremely rare. It still doesn't support HTML in subtitles, which was reported and asked I 7-8 years ago or something.

we don't play bluray discs
we just want to play our mkv files that use those codecs... and this splash 2.1 doesn't have them.. period

Dan,

m2ts file is not Blu-ray disk, it is just a file container, like mkv.
I think the reason that I can play m2ts and mkv files with DTS audio is because I have ffdshow installed. Try it and see if you can play your MKV files.